Analog gauges, otherwise known as meters or “clocks” have a pointer that sweeps across a dial in response to a monitored parameter. In time clocks, the hour hand of an analog clock goes around the clock face as the Earth rotates around its axis, or, from the viewer on Earth, as the Sun crosses the heavens.
In vehicles, for example, analog gauges that resemble clocks include fuel and temperature gauges, rev counters, speedometers, and the like. In such analog gauges, a needle or pointer moves across a linear scale, between a first extreme indicative of zero, signifying that the measured parameter is zero, be it an empty fuel tank, a cold engine, zero rev (revolution, i.e. pumping cycle of crankshaft) or zero speed, and a second extreme, or full scale deflection, that is indicative of full fuel tank, over heated engine, dangerously high revs, maximum speed, and the like.
Analog gauges are also used in airplanes and boats, and are also widely used in industry, to monitor temperature, pressures, flow rates and the like.
With reference to an analog vehicle speedometer, using such a gauge to visually monitor the speed of a vehicle may have many disadvantages. For example, if the driver looks at the speedometer to monitor his speed rather than concentrating on occurrences on the road, the driver is at least momentarily distracted and does not pay full attention to events happening on the road. The likelihood of an accident is increased. The process of repeatedly looking down at the various gauges, even if it is done only intermittently, is a wearing task and contributes to fatigue, especially on long rides. However, drivers who do not check the speed of their vehicle frequently may exceed the speed limit, or safe driving speeds. A driver inadvertently relaxing while driving might press more heavily on the accelerator pedal or reducing pressure, thereby increasing or decreasing the speed of the vehicle, without any warning being activated on such occasions. An alert such as an audible alarm noise, or some other indication regarding a velocity exceeding a predefined limit is, therefore, of great importance, and it will thus be appreciated that monitoring such clocks and gauges automatically and providing an audible or visual alert may improve driving safety, would help the driver to stay alert, improve confidence and keep driver focused on the road.
There is therefore, a need for a practical implementation of a device or system for monitoring gauges such as speedometers. Such an implementation should be retrofittable and should avoid interfering with the mechanical components of the vehicle, both to avoid damage and to prevent affecting the vehicle's warranty and/or insurance.
Prior art devices apparently do not satisfactorily address the problems involved in such systems. For example:
U.S. Pat. No. 6,748,322 to Fernandez, entitled “Speed monitoring device for motor vehicles” relates to a system for monitoring the speed and location of a vehicle over a given area by using a global positioning system and comparing the position fix and speed against a computerized map for the area containing predetermined limits for the speed and territory over predetermined times and days of the week. If a limit is exceeded the position fix and speed information is stored along with the time when it took place. The stored information can be optionally transmitted to a remote location for further processing. Also, alarm circuits are provided inside the vehicle to selectively alert the occupants that a limit has been exceeded.
U.S. Pat. No. 6,728,605 to Lash et al., entitled “Vehicle speed monitoring system and method” relates to a vehicle speed monitoring device which enables a driver to enter a speed tolerance profile that represents the driver's personal travel speed preferences and which alerts the driver when the vehicle speed falls outside the speed tolerance profile. Specifically, the speed tolerance profile consists of a number of speed tolerance ranges, each associated with a particular posted speed limit. As the vehicle travels through various map zones, the applicable posted speed limit is determined using a customized GPS map. The device determines the vehicle location, speed and the posted speed limit and then compares the vehicle speed using a running average to see whether vehicle speed is within the driver's speed tolerance profile, and, if not, the device provides the driver with a visual and/or audible warning according to the driver's operational preferences.
U.S. Pat. No. 6,515,596 to Awada, entitled “Speed limit display in a vehicle” relates to a method and apparatus for reporting a posted speed limit to the driver of a vehicle. The position of the vehicle is determined using a GPS receiver or triangulation of cellular telephone signals. The position is used to retrieve speed limit or other information from a database. The information is then reported to the driver. A technique is also disclosed for comparing the actual speed of the vehicle with the posted speed limit and issuing a warning to the driver when the posted speed limit is exceeded. All the above systems rely on GPS technology and can only work where GPS is supported.
U.S. Pat. No. 4,095,553 to Ono et al., entitled “Speedometer with an exceeding speed warning device” describes a lever fixed to a metal cap or speed cup of a speedometer that is vibratably engageable with projections provided on a rotating ring member when a speed pointer rotatable with the metal cap deflects beyond a predetermined maximum index, so that the speed pointer is vibrated to give a warning to the vehicle driver. The device described is a speedometer that might be provided with a vehicle, or retrofitted by a skilled mechanic to an existing vehicle, in lieu of the speedometer provided. It is not a device that can be easily retrofitted by a driver. The device does not address the issue of such gauges being distracting to the driver.
U.S. Pat. No. 3,980,041 to Evans, entitled “Speedometer with speed warning indicator and method of providing the same” describes an improved speed warning indicator for a speedometer comprises a transparent plate such as a transparent decal, having means such as an attached transparent plastic sheet bearing adhesive for attaching it to the transparent face cover of a speedometer casing containing a speedometer dial. The plate bears indicia, such as color and/or a plurality of spaced lines, etc. demarking the plate and the speedometer dial viewed through the plate, thereby indicating a speed warning on the dial while still permitting unobstructed viewing of all of the dial. Preferably, the plate is configured and dimensioned to overlie only a portion of the cover and dial so as to more clearly provide the speed warning. The plate can be affixed, in accordance with the present method, to the face cover of a fully assembled speedometer so as to provide very easily, simply and effectively, the improved speedometer of the invention. Though perhaps making the display of the speedometer easier to read, such a device has all the limitations of conventional speedometers, described hereinabove.
UK Patent Application No. 2,384,603 to Matharu, entitled “A speed alert device” describes a stick-like speed alert device that may be attached to the clock glass of a speedometer using vacuum suckers. The device includes a battery (dry cell), a proximity sensor and a buzzer and provides a buzzing noise when it detects that the needle (pointer) of the speedometer passes therebeneath. The device lacks enablement in that no explanation is given of how the proximity sensor senses a speedometer needle in its proximity. Additionally, such a tall protrusion extending from the speedometer, may, in itself, be a distraction to the driver, particularly since, of necessity, it is mounted off center, and ruins the symmetry of the dashboard.
U.S. Pat. No. 6,094,615 to Park, entitled “Speed limit control system and method for vehicles” describes a speed limit control system and method for vehicles, which can control both the amount of fuel injection and ignition timing of an engine so as to restrict speed more than a regulation speed. The system includes a vehicle speed sensor for generating electronic signals in accordance with an actual vehicle speed; a control device for judging the actual vehicle speed in accordance with signals from the vehicle speed sensor, outputting control signals for controlling ignition timing of an engine and the amount of the fuel injection in accordance with the speed variation in order not to exceed a predetermined regulation speed; an ignition device for igniting at a predetermined timing by signals, the signals being transferred from the engine control device; and an injection device for injecting the predetermined amount of fuel by signals, the signals being transferred from the engine control device. The system described monitors the revolution of the wheels of the vehicle directly using a magnetic sensor means and directly controls the speed. Such a system is expensive and limiting to the driver, and is difficult to override.
Dutch Patent Number NL 1008348C to George et al. entitled “an accessory for a vehicle speedometer” describes a retrofittable accessory that is attachable to the transparent cover plate of the speedometer by a suction pad. The accessory is positioned over the axis of rotation of the speedometer needle. The sensor is fitted to the end of a hinged radial carrier that is aligned with the required speed graduation and is then clamped. If the needle passes under the sensor, the sensor output triggers a circuit which produces an audible waning, which may be spoken message, such as “too fast”. The sensor may be moved from one position to another, but this has to be done manually. Such a system is good to set at the speed-limit before motorway cruising, for example, but cannot be readily used for providing appropriate warnings on different roads, such as in-town, inter-city and motor way.
U.S. Pat. No. 5,659,290 to Haeri, entitled “Speed minder”, relates to a universal device for vehicles which measures the speed of the vehicle and continuously displays the speed on a digital readout display located in the vicinity of the dashboard of the vehicle. A separate digital switch integrated into the circuitry of the device is used to pre-set a reference speed to a desired value. As the vehicle's actual speed exceeds this pre-set reference value, a buzzer sounds and/or the speed display flashes off and on to alert the driver that he has exceeded the pre-set speed. When the vehicle speed falls below the pre-set limit, the buzzer and flashing stops and the device acts as a regular digital speedometer. The device is adjustable, thus enabling it to be used on a wide variety of vehicles.
Haeri's sensing means is a magnetic proximity sensor that comprises a reed switch sensor surrounded by a non-magnetic metal sleeve, made, for example, from copper, aluminum, etc. The sensor requires that the pointer of the speedometer be ferro-magnetic. For weight minimization, such pointers are, however, frequently plastic or aluminium.
French Patent 9504565 to Bruch, entitled “Avertisseur de vitesse” and French Patent 89 13871 to Poulain, entitled “Procede de detection du positionnement relatif d'un indicateur a aiguille, et dispositif electronique permettant de la mettre en oeuvre” both describe sensors for sensing the position of the needle of a speedometer. Apparently a light source is provided for illuminating a spot thereunder, and the passage of the needle is detected by a change in the signal.
The sensors described by Haeri, Bruch and Poulain, like many others described hereinabove, are capable of providing simple yes/no information regarding passage of a pointer thereunder, and does not allow tracking of the pointer, or monitoring at two speeds, for example.
U.S. Pat. No. 5,554,970 to Mottahedeh, entitled “Speed alert system for an automobile” describes a speed alarm system for an automobile comprised of a first circular disk having a semi-circular electronic indicator grid formed around an outer periphery thereof. The first circular disk is rotatably positioned on a speedometer relay of an automobile and coupled thereto by a knob portion. A second circular disk has a circular recess formed therein inwardly of an outer periphery thereof. The second circular disk is positionable through an upper portion of the knob portion whereby the semi-circular electronic grid of the first circular disk is in selective alignment with the circular recess of the second circular disk. An indicating needle has a first end rotatably coupled with the upper portion of the knob portion. A second end has a magnetic portion extending downwardly through the circular recess of the second circular disk. A speaker has wiring extending outwardly thereof to couple with the existing speedometer relay of the automobile and with the semi-circular electronic grid of the first circular disk. The device to Motadeh appears to be a replacement for the traditional speedometer, requiring fitting by a skilled mechanic.
GB Patent No. 2,360,582 to Herrington, entitled “Vehicle excessive speed monitor” describes a monitor for warning a driver of excessive speed or revs. The monitor has a light source in a housing that is attached to the clear screen above a vehicle instrument panel by adhesive or suction cups. Behind the light source is the monitoring circuitry, a battery, and an audible warning device that produces an audible tone to alert the driver when the light beam is broken by the speedometer or rev counter needle. The monitor is detachable and may be positioned for a particular speed limit, e.g. 30 mph.
U.S. Pat. No. 6,600,409 to Cohen, entitled “Signaling self-contained add-on accessory for an analog metering device such as a speedometer and secondary device” relates to a self-contained accessory for an analog metering device such as a speedometer or tachometer. The accessory includes a sensor which is selectively adjustable to align with a plurality of positions in the range of movement of an output needle of the analog metering device. In the preferred embodiment, the sensor is alignable with gradation marks, e.g., miles per hour indicia on a speedometer, and the accessory provides a signal when a needle reaches a selected gradation. The signal is sent to a secondary device, such as a radar detector or central monitoring system. The signal may also be used to provide an indication that alerts a user that a selected gradation has been reached by an output needle of the analog metering device. The accessory attaches to a cover of the analog metering device and allows adjustment of sensor position without removal of the accessory from the cover. A preferred radar detector uses the signal to effect a modified operation where some functions of the radar detector are responsive to the signal of the accessory. The device described is essentially a self-contained add-on accessory for an analog metering device, that has a needle with a sensor that detects the alignment of the needle of accessory with needle of metering device.
U.S. Pat. No. 6,310,544 to Cohen, entitled “Self-contained add-on accessory for an analog metering device such as a speedometer or tachometer” relates to a self-contained add-on accessory for an analog metering device having a moving needle as an indicator of a measured output parameter, the accessory comprising: a housing dimensioned to fit on a portion of a cover of the analog metering device without obscuring gradation marks on a face of the analog metering device; a selectively adjustable member extending from the housing and alignable with a plurality of different gradation marks on the face of the analog metering device; a sensor mounted in associated with said selectively adjustable member to detect when an output needle of the analog metering device reaches a gradation on the face of the analog device with which said selectively adjustable member has been aligned; and a power source within said housing for powering said sensor.
Despite the crowded art, there is still a need for a device for automatically reading analog gauges such as speedometers, and the present invention addresses this need.